#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
using namespace std;

int main()
{
	string str;
	cin >> str;
	for (int i = 0;i < str.length()-1;i++)
	{
		printf("%c", str[i] + str[i + 1]);
	}
	printf("%c", str[0] + str[str.length() - 1]);
	return 0;
}